IBM 4690 OS

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IBM 4690 OS, sometimes shortened to 4690 OS or 4690, is a retail-focus computer operating system that much resembles DOS in interface and interaction. This proprietary operating system is offered by IBM to retail customers for operating its Supermarket Application (SA), General Sales Application (GSA), Chain Drug Sales Application (CDSA), and ACE retail platforms is based on the Flex OS, originally developed by Digital Research. Though the 4690 operating system resembles DOS, much of its internal functions and behavior are much like the commercial UNIX operating systems.

The majority of large grocery retailers are using the 4690 operating system in one form or another for their operations because of its features in the grocery retail business. While not all of these retailers elect to use the IBM 4690 terminals, enhancements from third-party companies like QVS software and NCR have helped to allow things like NCR RealPOS registers, NCR self checkout terminals, and ECS/Fujitsu self checkout terminals to interface with the 4690 operating system.

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[edit] Hardware requirements

In order to make the 4690 operating system marketable for IBM, and IBM alone, hardware requirements and seemingly limited device drivers are used so that specific IBM hardware is required. Most notably, the use of an "NVRAM" card is required and these cards only work with specific IBM-manufactured servers. The NVRAM card, which is either a Store Loop Adapter (for connecting to proprietary IBM Store Loop Networks) or an NVRAM module card, is required for holding the device address of the system running the 4690 address and for providing memory for file-handling functions (primarily the Power Line Disturbance feature of the OS, which protects file writing from power-loss by queuing it until it is completely written). IBM provides a "Controller Matrix" document with a list of compatible IBM servers for use with 4690 OS.

[edit] System interface

The 4690 operating system's interface, as mentioned above, is much like DOS. However, typical users are not greeted with a command prompt and required to enter commands. The 4690 operating system boots to a welcome screen where you enter a login ID and password. After this, most functions for the majority of users are menu-driven. One of the most popular 4690 software packages, the Supermarket application, is completely menu-driven by selecting numeric menu items and navigating using the Enter and F-keys. Unlike DOS, the 4690 operating system supports background applications that can be pre-configured to run at boot. These are controlled by the background applications screen.

[edit] Notable features and usability

One of the most notable things about the 4690 operating system is its ability to provide a "redundancy infrastructure". IBM designed the 4690 OS to work on one machine with one or more other 4690 servers. Machines running 4690, commonly called "controllers", are assigned an ID that is stored in the NVRAM card. This typically follows the convention of CC, DD, etc and must be two letters. When put together with other 4690 boxes, a machine running 4690 will begin exchanging packets and will associate itself with the other systems if their "Store Number" matches. There will be a machine that is pre-designated as a "Master" and either the same or another machine pre-designated as the "File Server". These machines control communications functions and provide various network-based services. The "File Server" machine is the actual location of the currently active application files. This machine will have a "Alternate File Server", which will have an exact mirror of distributed application files in case of failure. The system also contains a "Master" machine, which has control of the OS files, and an "Alternate Master" with the mirrored OS files. Any other machine on the system is a "Subordinate" machine, and only gets updates to files. Any one of these machines can have "TCC" (terminal communications control), or "TCC Backup" as a fail over, configured. If the machine configured as TCC controller goes offline, the TCC Backup machine takes control of the terminals. If "AutoResume" is configured for the TCC controller for a terminal and the TCC controller comes back online, that terminal will come out of "Backup" and into a normal state. If both the TCC and TCC Backup controllers go offline, the terminal will go into an offline state. 4690 can be configured for terminals to run from a local terminal based item file in a "Terminal Offline" state.

Another notable feature of the 4690 operating system is that it is extremely stable. While not extremely advanced with technology, the 4690 operating system has been in use by a number of retailers for many years and has gained a reputation for extreme reliability.

[edit] Technology and software

To anyone who has used the 4690 operating system, it is obvious that it is not the most up-to-date on current technologies or software support. Just recently, IBM, with 4690 operating system version 5, has incorporated new security enhancements, such as SSH (which is actually a telnet interface piggy-backing over a SSH connection) and enhanced operator security (allowing alpha-numeric operator IDs, password complexity requirements, password expiration, etc). These features, prior to OSv5, were not available. In order to retain the marketable value of the 4690 operating system, IBM heavily guards knowledge of building applications for the operating system and has developed proprietary languages for use on the system. One such language is IBM CBASIC, which resembles the BASIC language, but has a lot of the familiar earmarks of a C-based language (memory handling, etc). 4690 also supports Metaware High-C and strict versions of the Java language. With Metaware High-C, the developer must use a special IBM toolkit with libraries for 4690 to develop and compile applications on other operating systems (or use the tools on the 4690 OS). Starting with OSv3, IBM included support for Java applications to run on 4690. With this enhancement, IBM has allowed a now open-source language to operate on its operating system. Although this seems like a great step, in keeping with IBM fashion, the Java development on the 4690 platform is far from standard and basically molests the very nature of Java development in general. To learn more, simply attend an IBM workshop on Java application development for 4690.

[edit] Sources

Published sources of the information above include the following IBM Publications:

These documents can be obtained from IBM at the Retail Publications Download Center.

Unpublished sources of the information above include the following:

  • Hands-on experience and work in troubleshooting and configuring this software from this document's author.